A shaft is a circular cross sectional with diameter of 1.5" is subjected to loading of bending Mz = 5000 lb-in and a torque of T=8000 lb in and an axial tensile force of F = 6000 lf. if the material has a yield strength of Sy= 40 kpsi, find safety design factor for (a) maximum shear stress theory criterion, and (b) von mises theory.